Allegro 5 api
#include <allegro5/allegro.h> void al_unref_user_event(ALLEGRO_USER_EVENT *event)
Decrease the reference count of a user-defined event. This must be called on any user event that you get from al_get_next_event(3alleg5), al_peek_next_event(3alleg5), al_wait_for_event(3alleg5), etc. which is reference counted. This function does nothing if the event is not reference counted.
al_emit_user_event(3alleg5), ALLEGRO_USER_EVENT(3alleg5)